There are three ways for you to implement the Word Add-In for you and your organization.
If your organization allows individual users to install Add-Ins, then installing via the Microsoft AppSource is your best route.
Install via Microsoft AppSource
For an individual, wanting to learn how to install themselves, see also: How do I download the Word Add-On?
If your organization requires tighter authorization, your IT department can use one of the following options.
Install via Microsoft 365 Admin Center
Install via Sharepoint Catalog